Cat & LPG

[tuv]

Hi I'd like to now:

if youv'e been converted to LPG (only runs on petrol for a cople of mins in the morning) do you need a cat fitted. (98 Grand Cherokee)

Thanks!!

[rsd2525]

Hi, i used to have 2 old cars that ran on lpg neither had a cat, now i have a peugeut 406 which i had converted, no probs, so i would assume it doesn't matter either way. Hasn't the 98 GC got a cat ?

[tuv]

Yes it's got a cat but it's died on me and it needs a new one.

[rsd2525]

yes you must fit a cat or the sensors wont read and your brain box will flip its lid

[tuv]

Thanks!!

i'll have to ask santa for a new one

[DirtyHabit]

I would check with your MOT tester. I believe that the vehicle is tested on which ever fuel it is running on when presented for MOT. I own several US built vehicles which are converted to LPG, and on mine the sensors are fitted before the cat and so readings are taken before the gases reach the cat. Again I would check with your tester it may be down to readings and the presents of the cat may not be relevant. But there may be a legal requirement for one to be fitted.

[lebesset]

the construction and use regs say that it is illegal to remove emissions control equipment
but if it is correct that the tester will test on whatever fuel it is presented on ,you present it on lpg, and it will pass the CAT standard on that , then you will get your mot pass ; after all , you didn't remove the CAT , did you , the mot man cannot test it's efficency , only the emissions
there is no connection between the O2 [ lambda ] sensor and the CAT , they are always fitted pre CAT
so just ring the mot station , check they will test on lpg if you present it like that ; if your lpg is working correctly , it will pass easily , CAT or no CAT